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They are the most common type of volcanoes. Many cinder cones have a bowl-shaped crater at the summit. They are commonly found on the flanks of shield

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Page 1: They are the most common type of volcanoes. Many cinder cones have a bowl-shaped crater at the summit. They are commonly found on the flanks of shield
Page 2: They are the most common type of volcanoes. Many cinder cones have a bowl-shaped crater at the summit. They are commonly found on the flanks of shield
Page 3: They are the most common type of volcanoes. Many cinder cones have a bowl-shaped crater at the summit. They are commonly found on the flanks of shield

• They are the most common type of volcanoes.

• Many cinder cones have a bowl-shaped crater at the summit.

• They are commonly found on the flanks of shield volcanoes, strato volcanoes, and calderas.

• Geologists have identified nearly 100 cinder cones on the flanks of Mauna Kea, a shield volcano located on the island of Hawaii.

• They are smaller and simpler than composite volcanoes.

• It forms when ash, cinders and bombs pile up around the vent to form a circular or oval cone.

• “Cinders are melted volcanic rock that cooled and formed pebble-sized pieces when it was thrown out into the air.”

Page 4: They are the most common type of volcanoes. Many cinder cones have a bowl-shaped crater at the summit. They are commonly found on the flanks of shield

• “They are ejected from a single vent and accumulate around the vent when they fall back to earth.”

• “Cinder cones can occur alone or in small to large groups or fields.”

• “Most have a bowl-shaped crater at the summit.”

• “The longer the eruption, the higher the cone.”• The shape of a cinder cone can be modified

during its (short) life. • “Cinder cones are built from lava fragments

called cinders.  The lava fragments are ejected from a single vent and accumulate around the vent when they fall back to earth.”

Page 5: They are the most common type of volcanoes. Many cinder cones have a bowl-shaped crater at the summit. They are commonly found on the flanks of shield

“A cinder cone or scoria cone is a steep conical hill of volcanic fragments that accumulate around and downwind from a volcanic vent. The rock fragments, often called cinders or scoria, are glassy and contain numerous gas bubbles "frozen" into place as magma exploded into the air and then cooled quickly. Cinder cones range in size from tens to hundreds of meters tall. Cinder cones are made of pyroclastic material.”

Page 6: They are the most common type of volcanoes. Many cinder cones have a bowl-shaped crater at the summit. They are commonly found on the flanks of shield

• Also called strato volcanoes • Formed by alternating layers of lava and rock fragments • Often have snow capped peaks• Between eruptions, they seem extinct because they are very

quiet• Eruption is explosive• Caused by viscous magma• When the magma rises, it clogs the opening. This results in

gas building up until it explodes

Page 7: They are the most common type of volcanoes. Many cinder cones have a bowl-shaped crater at the summit. They are commonly found on the flanks of shield

• Can grow about 8,000 ft above bases• Can grow very large but the sides weaken too much that

the volcano collapses because of gravity• Many located on the “Ring of Fire”• Volcanoes form when an oceanic plate boundary and a

continental plate boundary meet. The oceanic goes under the continental because it is denser. This is called subduction. Then hot magma rises and forms a volcano.

• They occur because the plates are moving. Underneath the crust, convection is circling around causing the plates to move and crash into each other.

Page 8: They are the most common type of volcanoes. Many cinder cones have a bowl-shaped crater at the summit. They are commonly found on the flanks of shield

• Shield volcanoes are big and made up of fluid lava flows.• They get their name because the sloping hills that surround

them have a fan shaped pattern that looks like a shield.• They have broad, sloping sides.• Shield volcanoes are formed from the action of the gas or

steam or water vapor with heat from the earth’s core. This melts rock turning it into magma. The pressure from the heat of the gas pushes the magma up until it explodes. Molten Magma shoots upward from under the ocean floor and breaks through the plates and forms a shield volcano.

Page 9: They are the most common type of volcanoes. Many cinder cones have a bowl-shaped crater at the summit. They are commonly found on the flanks of shield

• Shield volcanoes could be made from hot spots under the surface.

• Shield volcanoes are built up of effusive eruptions.• Shield volcanoes measure to about 3-4 miles in

diameter.• They measure up to 1,500-2,000 feet high.

Page 10: They are the most common type of volcanoes. Many cinder cones have a bowl-shaped crater at the summit. They are commonly found on the flanks of shield

Diagram of a Hawaiian eruption (key: 1. Ash plume 2. Lava fountain 3. Crater 4. Lava

lake 5. Fumaroles 6. Lava flow 7. Layers of lava and ash 8. Stratum 9.Sill 10. Magma conduit 11. Magma chamber 12.Dike) Click for larger version

Page 11: They are the most common type of volcanoes. Many cinder cones have a bowl-shaped crater at the summit. They are commonly found on the flanks of shield

• When a volcano explodes, houses, buildings, roads, and fields can get covered with ash. People will often evacuate their houses. If the ash is really heavy, it can make it hard, or impossible, to breathe.

Page 12: They are the most common type of volcanoes. Many cinder cones have a bowl-shaped crater at the summit. They are commonly found on the flanks of shield

• The most destructive volcano is Mt. Tambora in Indonesia. It was an active composite volcano that occurred on April 5th 1815. It killed 12,000 people directly from the volcano, and 80,000 killed from starvation afterward. That is a total of 92,000 people killed!

Page 13: They are the most common type of volcanoes. Many cinder cones have a bowl-shaped crater at the summit. They are commonly found on the flanks of shield

Videos

• http://www.youtube.com/watch?v=7as7Ej_U6yU

• http://www.youtube.com/watch?v=TRX3LkcGrb0

Page 14: They are the most common type of volcanoes. Many cinder cones have a bowl-shaped crater at the summit. They are commonly found on the flanks of shield
Page 15: They are the most common type of volcanoes. Many cinder cones have a bowl-shaped crater at the summit. They are commonly found on the flanks of shield

Today two million people live in the immediate vicinity of Mount Vesuvius. This mountain has erupted more than 50 times since the eruption in 79 A.D., when it buried Pompeii and its sister city, Herculaneum. After Pompeii was buried and lost to history, the volcano continued to erupt every 100 years until about 1037 A.D., when it entered a 600 year period of quiescence.

The 79 A.D. eruption of Vesuvius was the first volcanic eruption ever to be described in detail. From 30km (18 miles) west of the volcano, Pliny the Younger, witnessed generate high-altitude eruption columns and blanket large areas with ash. It is estimated that at times during the eruption the column of ash was 32 km (20 miles) tall. About 4 cubic kilometers (1 cubic mile ) of ash was erupted in about 19 hours. Volcanoes by Peter Francis contains several direct passages from Pliny the Younger and describes the archeology of Pompeii and Herculaneum. Copyrighted photograph of a street in Pompeii by Robert Decker, 1971 the eruption and later recorded his observations in two letters. He described the earthquakes before the eruption, the eruption column, air fall, the effects of the eruption on people, pyroclastic flows, and even tsunami. Volcanologists now use the term "plinian" to refer to sustained explosive eruptions which. Vesuvius is in the background.

Mudflows and lava flows from the eruption in 1631 killed 3,500 people. Studies of past eruptions and their deposits continue. These studies help volcanologists understand the hazards associated with future eruptions. The population density in some areas of high risk is 20,000 to 30,000 per square km (7,723 to 11,584 miles per square km). About 3 million people could be seriously affected by future eruptions. In the first 15 minutes of a medium- to large-scale eruption an area with a 7 km (4 mile) radius of the volcano could be destroyed (Dobran and others, 1994). About 1 million people live and work in this area.

Page 16: They are the most common type of volcanoes. Many cinder cones have a bowl-shaped crater at the summit. They are commonly found on the flanks of shield

Composite Volcanoes• Mount St. Helens - Washington State• Mount Rainier - Washington State• Mount Vesuvius – Italy• Mayon Volcano - Luzon Island, Philippines• Mount Fuji – Japan• Mount Cotopaxi – Ecuador• Mount Shasta – California• Mount Hood – Oregon

Cinder Cone Volcanoes• Cinder Cones and Scoria Cones • California Cinder Cones • Cerro Negro, Nicaragua • Lava Butte, Oregon • Newberry Caldera Vicinity, Oregon • New Mexico Cinder Cones • Paricutin, Mexico • Portland Vicinity, Oregon • Sunset Crater, Arizona • Wizard Island, Crater Lake, Oregon

Shield Volcanoes·Kilauea (Hawaii) ·Mauna Loa (Hawaii) ·Etna (Sicily) ·Piton de la Fournaise (Reunion) ·Erta Ale (Ethiopia) ·Fernandina and all Galapagos volcanoes ·Nyamuragira (Congo) ·Karthala (Indian Ocean) ·Savai’i (Samoa) ·Aoba (Vanuatu)

Page 17: They are the most common type of volcanoes. Many cinder cones have a bowl-shaped crater at the summit. They are commonly found on the flanks of shield
Page 18: They are the most common type of volcanoes. Many cinder cones have a bowl-shaped crater at the summit. They are commonly found on the flanks of shield

• http://library.thinkquest.org/17457/volcanoes/types.composite.php • http://www.weatherwizkids.com/weather-volcano.htm • http://www.k12.hi.us/~kapunaha/student_projects/volc_blowout/composite_volcano.htm• http://www.pdc.org/iweb/volcano_deadliest1.jsp • http://www.k12.hi.us/~kapunaha/student_projects/volc_blowout/cinder_cone_volcano.htm• http://en.wikipedia.org/wiki/Cinder_cone • http://library.thinkquest.org/17457/volcanoes/types.cinder.php • http://www.cotf.edu/ete/images/modules/volcanoes/typesc.GIF • http://geology.com/volcano/sp-crater.jpg • http://canarygeog.canaryzoo.com/Geog1/composite%20volcano.jpg • http://volcanoes.usgs.gov/Imgs/Jpg/Photoglossary/shieldvolcano1_large.jpg • http://library.thinkquest.org/06aug/00886/index_files/Page307.htm• http://vulcan.wr.usgs.gov/Glossary/CinderCone/description_cinder_cone.html

Page 19: They are the most common type of volcanoes. Many cinder cones have a bowl-shaped crater at the summit. They are commonly found on the flanks of shield